You should use one of the computer algebra systems below with this example. Click on the appropriate icon for your preferred CAS and then arrange your screen so that you can easily move back-and-forth between this window and your CAS window. Click on the appropriate help button for help.
The Average Daily Number of Sunspots
Year Average | Year Average | Year Average | Year Average
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1749 80.93 | 1806 28.11 | 1863 44.02 | 1920 37.64
1750 83.39 | 1807 10.05 | 1864 46.95 | 1921 26.13
1751 47.66 | 1808 8.14 | 1865 30.48 | 1922 14.24
1752 47.80 | 1809 2.53 | 1866 16.29 | 1923 5.78
1753 30.69 | 1810 0.00 | 1867 7.26 | 1924 16.72
1754 12.22 | 1811 1.42 | 1868 37.29 | 1925 44.31
1755 9.57 | 1812 4.95 | 1869 73.90 | 1926 63.89
1756 10.19 | 1813 12.19 | 1870 139.11 | 1927 69.04
1757 32.43 | 1814 13.93 | 1871 111.20 | 1928 77.79
1758 47.60 | 1815 35.40 | 1872 101.67 | 1929 64.97
1759 53.97 | 1816 45.81 | 1873 66.29 | 1930 35.67
1760 62.86 | 1817 41.06 | 1874 44.65 | 1931 21.23
1761 85.85 | 1818 30.06 | 1875 17.07 | 1932 11.14
1762 61.15 | 1819 23.94 | 1876 11.32 | 1933 5.66
1763 45.12 | 1820 15.67 | 1877 12.28 | 1934 8.72
1764 36.35 | 1821 6.59 | 1878 3.37 | 1935 36.06
1765 20.91 | 1822 4.00 | 1879 5.96 | 1936 79.73
1766 11.41 | 1823 1.79 | 1880 32.27 | 1937 114.40
1767 37.83 | 1824 8.54 | 1881 54.25 | 1938 109.55
1768 69.84 | 1825 16.57 | 1882 59.65 | 1939 88.75
1769 106.09 | 1826 36.28 | 1883 63.70 | 1940 67.78
1770 100.80 | 1827 49.71 | 1884 63.45 | 1941 47.48
1771 81.58 | 1828 64.15 | 1885 52.16 | 1942 30.60
1772 66.49 | 1829 67.03 | 1886 25.37 | 1943 16.32
1773 34.78 | 1830 70.98 | 1887 13.05 | 1944 9.59
1774 30.62 | 1831 47.81 | 1888 6.75 | 1945 33.09
1775 7.01 | 1832 27.52 | 1889 6.27 | 1946 92.51
1776 19.82 | 1833 8.53 | 1890 7.05 | 1947 149.84
1777 92.50 | 1834 13.24 | 1891 35.62 | 1948 136.20
1778 154.37 | 1835 56.86 | 1892 72.97 | 1949 135.12
1779 125.93 | 1836 121.45 | 1893 84.93 | 1950 83.92
1780 84.80 | 1837 138.28 | 1894 78.01 | 1951 69.76
1781 68.09 | 1838 103.15 | 1895 63.97 | 1952 31.41
1782 38.46 | 1839 85.82 | 1896 41.78 | 1953 13.85
1783 22.80 | 1840 63.19 | 1897 26.24 | 1954 4.41
1784 10.17 | 1841 36.80 | 1898 26.72 | 1955 37.95
1785 24.10 | 1842 24.19 | 1899 12.11 | 1956 141.71
1786 82.87 | 1843 10.68 | 1900 9.46 | 1957 189.85
1787 132.03 | 1844 15.00 | 1901 2.74 | 1958 184.59
1788 130.91 | 1845 40.06 | 1902 5.02 | 1959 158.75
1789 118.11 | 1846 61.50 | 1903 24.38 | 1960 112.28
1790 89.89 | 1847 98.46 | 1904 41.95 | 1961 53.90
1791 66.58 | 1848 124.32 | 1905 63.47 | 1962 37.60
1792 60.04 | 1849 95.87 | 1906 53.86 | 1963 27.89
1793 46.90 | 1850 66.53 | 1907 62.03 | 1964 10.20
1794 41.00 | 1851 64.50 | 1908 48.54 | 1965 15.06
1795 21.27 | 1852 54.21 | 1909 43.88 | 1966 46.88
1796 16.02 | 1853 39.02 | 1910 18.58 | 1967 93.67
1797 6.39 | 1854 20.57 | 1911 5.70 | 1968 105.89
1798 4.07 | 1855 6.71 | 1912 3.59 | 1969 105.56
1799 6.76 | 1856 4.30 | 1913 1.44 | 1970 104.69
1800 14.48 | 1857 22.78 | 1914 9.59 | 1971 66.65
1801 34.00 | 1858 54.81 | 1915 47.37 | 1972 68.93
1802 45.03 | 1859 93.83 | 1916 57.07 | 1973 38.15
1803 43.05 | 1860 95.69 | 1917 103.89 | 1974 34.41
1804 47.47 | 1861 77.17 | 1918 80.58 | 1975 15.46
1805 42.24 | 1862 59.11 | 1919 63.61 | 1976 12.55
The same data is given in your CAS window. Use your CAS window to draw a graph showing this data. The TI-92 screen shows this data as graphed using the TI-92.
Notice that this data seems to vary more-or-less periodically. Roughly, what does the period appear to be? Would you expect this kind of data to exhibit very precise periodic behavior? Why? or Why not?